About one month ago my hard disk (SATA II Seagate Barracuda 1Tb 7200 rpm) started making a clicking sound: a sort of loud tic-tac, every second or so, when involved in disk activity. The system was clearly slower than before at disk access, but it was functional and I could not find any signal of trouble on the linux logs. I disconnected the disk and tried an older SATA drive I had around: no problem with it. Then I reconnected the Seagate disk, and the problem was mysteriously gone. Ubuntu booted normally, usual speed, no clicking.

A couple of weeks later, the problem reappeared. I tried disconnecting reconnecting (as it somehow solved the problem before) without luck. So, despite it was a rather new drive, I assumed it was a hardware issue, made backups and bought a new drive.

The new drive is a SATA II Seagate Barracuda 1.5 Tb 7200 rpm. I installed both drives at the same time, with the intention of transferring my files from on to the other. To my surprise, when I booted the computer with both drives, both started making the clicking sound !! Even worse, I removed the old drive, leaving the unformated new drive connected, and booted from a LiveCD. It kept clicking !

Puzzled by this, I tried both drives on my laptop with a SATA to USB cable. At the moment I connected any of them, they made one or two unusual clicks and immediately stopped doing that and worked normally. The old drive I thought almost dead, was working like a charm as if nothing happened.

Then I thought: "ok, it must be the motherboard. Let's try again". So, I reconnected the old drive to the ASUS P6T motherboard (the same cables and SATA port as before), and it worked as if nothing happened ! The problem was gone again. The new 1.5 Tb drive was also working ok: No clicking nor slowdown.

So I left the old 1Tb disk connected and kept using the computer daily during 3 weeks, until today it happened again. Now I don't really know what to do or check. I'm not even sure if it is a hardware issue any more !

This is rather annoying as it seems it happens with a period of 2 or 3 weeks and I have no means of forcing it to happen. Does anyone have a clue of what can causes this behaviour or have any suggestions of things I should check when it happens again ?

What I did today is checking some SMART parameters

Error log: smartctl -l error /dev/sda. No errors

Short selftest: smartctl -t short /dev/sda. No errors

Disk Health check: smartctl -H /dev/sda. passed

And here are the vendor specific parameters (smartctl -A /dev/sda) Which I'm not quite sure how to interpret.